Electrode membrane assembly having an oxygen evolution catalyst electrodes, and methods of making and using the same

Patent metadata

Field	Value
Publication number	US-2018358641-A1
Application number	US-201615575454-A
Country	US
Kind code	A1
Filing date	May 4, 2016
Priority date	May 26, 2015
Publication date	Dec 13, 2018
Grant date	—

Abstract

Electrode membrane assembly having an oxygen evolution reaction electrodes, the electrode membrane assembly comprising nanostructured whiskers with at least one of metallic Ir or Ir oxide thereon. These oxygen evolution reaction electrodes when paired with suitable hydrogen evolution electrodes are useful, for example, in generating H 2 and O 2 from water.

First claim

1 . An electrode membrane assembly having an oxygen evolution reaction electrode, the electrode membrane assembly comprising, in order:
an ion conducting membrane having first and second generally opposed major surfaces; nanostructured whiskers with an oxygen evolution reaction electrocatalyst thereon, the electrocatalyst comprising at least one layer, wherein any layer of the oxygen evolution reaction electrocatalyst comprises collectively at least 95 atomic percent Ir, and not greater than 5 atomic percent Pt, based on the total collective cation and elemental metal content of the respective layer; and a first fluid transport layer comprising an electrically conductive, corrosion resistant, porous metal,
wherein the nanostructured whiskers are adjacent to the first major surface of the ion conducting membrane, and wherein the ion conducting membrane, the nanostructured whiskers having the oxygen evolution reaction electrocatalyst thereon, and the first fluid transport layer collectively have an electrical conductance of at least 0.1 S·cm −2 as measured in Example 2.

2 . The electrode membrane assembly of claim 1 , wherein the Ir is present at least in part as Ir oxide.

3 . The electrode membrane assembly of claim 1 , wherein the oxygen evolution reaction catalyst comprises not greater than 0.001 atomic percent Pt, based on the total collective cation and elemental metal content of the respective layer.

4 . The electrode membrane assembly of claim 1 , wherein the first fluid transport layer comprises Ti.

5 . The electrode membrane assembly of claim 1 , wherein the ion conducting membrane comprises a proton exchange membrane.

6 . The electrode membrane assembly of claim 1 , wherein the nanostructured whiskers comprise organic pigment perylene red.

7 . The electrode membrane assembly of claim 1 , wherein the nanostructured whiskers are at least partially embedded in the ion conducting membrane.

8 . The electrode membrane assembly of claim 1 , wherein the oxygen evolution reaction electrocatalyst is a continuous layer on the nanostructured whiskers.

9 . An electrochemical device comprising electrode membrane assembly claim 1 .

10 . The electrochemical device of claim 9 , further comprising a hydrogen evolution reaction catalyst adjacent the second major surface of the ion conducting membrane and an electrically conducting second fluid transport layer in electrical contact with the hydrogen evolution reaction catalyst.

11 . The electrochemical device of claim 10 , wherein the hydrogen evolution reaction catalyst comprises nanostructured whiskers having a major surface with a hydrogen evolution reaction electrocatalyst comprising Pt thereon.

12 . The electrochemical device of claim 9 , wherein the device is a water electrolyzer.

13 . The electrochemical device of claim 9 , wherein the device is a CO 2 electrolyzer.

14 . A method of generating hydrogen and oxygen from water, the method comprising:
providing an electrode membrane assembly of claim 1 , the electrode membrane assembly comprising an anode and a cathode catalyst, the anode being the oxygen evolution reaction electrode, and the cathode catalyst being adjacent to the second major surface of the ion conducting membrane; providing water in contact with the anode; and providing an electrical potential with sufficient current across the membrane electrode assembly to convert at least a portion of the water to hydrogen and oxygen on the cathode and anode, respectively.

15 . The electrode membrane assembly of claim 1 , wherein the ion conducting membrane has an equivalent weight less than or equal to 1200 equivalents per gram.

16 . The electrode membrane assembly of claim 1 , wherein the ion conducting membrane has and a thickness less than or equal to 50 micrometers.

17 . The electrode membrane assembly of claim 1 , wherein the ion conducting membrane comprises a highly fluorinated polymer electrolyte.

18 . The electrode membrane assembly of claim 11 , wherein the highly fluorinated polymer electrolyte is a perfluorosulfonic acid.

19 . The electrode membrane assembly of claim 1 , wherein the Ir loading in the catalyst layer is at least 0.125 mg/cm 2 .

Assignees

• 3M Innovative Properties Co

Inventors

• Lewinski Krzysztof A
• Luopa Sean M

Classifications

• C25B11/097

  comprising two or more noble metals or noble metal alloys · CPC title

• H01M4/9016

  Oxides, hydroxides or oxygenated metallic salts · CPC title

• C25B9/10

  Chemistry & Metallurgy · mapped topic

• H01M4/8807

  Gas diffusion layers · CPC title

• H01M8/1004 Primary

  characterised by membrane-electrode assemblies [MEA] (H01M8/12 takes precedence) · CPC title